1. Field of the Invention
The invention relates to outdoor ponds. More particularly, the invention relates to an apparatus for filtering pond water and skimming the surface of the pond.
2. State of the Art
Ponds have always been a desirable landscaping feature, particularly in conjunction with gardens. Until recently, however, artificial ponds have been relatively expensive to construct. With the advent of fish-safe polymer liner material that can be formed into any convenient shape, and covered with rock strata, natural looking artificial ponds have become a popular landscape feature.
Both natural and artificial ponds require maintenance in order to remain aesthetically pleasing. Ponds should also provide a habitat not only for fish but other creatures such as birds, frogs, butterflies and the like. Clear water is the feature most desired in ponds so that fish and submerged plants may be viewable. However, maintaining the clarity of the water can be difficult. Algae, in particular free swimming algae, may cause the water to become cloudy. The excessive algae typically occurs when the water contains an excess of nutrients such as ammonia and phosphorous. This ammonia and phosphorous is generally added to pond water by fish waste and fertilizer runoff from the land surrounding the pond. Although aquatic plants may consume a portion of the nutrients, the number of plants is typically insufficient to handle the amount of excessive nutrients in a pond. Algae, which feed on these nutrients, then multiply due to the abundance of nutrients. This multiplication may result in algae xe2x80x9cbloomsxe2x80x9d which cause the pond water to cloud.
One method of clarifying water is to add chemicals to the water which destroy algae. However, these chemicals may destroy or have a negative impact on the number and growth of aquatic plants and fish. Also, chemicals must be replenished and this can be expensive.
An additional maintenance problem involves the removal of leaves and other foliage which fall onto the surface of the pond. Unless it is soon removed from the surface, this foliage settles to the bottom where it decompose forming a layer of sludge. The sludge may reduce the depth of the pond and may also cover underwater formations. Removing the sludge requires draining the pond, a drastic procedure which requires temporary storage of fish and threatens the life of aquatic plants.
With these issues in mind, several companies have looked to the art of swimming pool maintenance in an effort to design apparatus for filtering pond water and skimming the pond surface. Typical solutions based on swimming pool technology are disclosed in U.S. Pat. Nos. 5,584,991 and 6,054,045 to Wittstock et al. One of the main disadvantages of these solutions is that they require excavation and permanent installation. In many cases, these solutions must be installed when the pond is first constructed because pipes need to be laid beneath the pond. In addition, these solutions require that relatively large apparatus be arranged adjacent to the pond. These unsightly apparatus must be camouflaged with stones, shrubs, etc.
The applicant herein has looked beyond swimming pool technology to provide the Pondmaster(copyright) filter system. The applicant""s Pondmaster(copyright) filter system is fully submersible in an existing pond, does not require any excavation, and does not require unsightly apparatus to be located adjacent to the pond. It is modular and can be expanded to suit ponds of different sizes. However, the Pondmaster(copyright) system does not include a skimmer.
It is therefore an object of the invention to provide a combined filter and skimmer assembly for ponds.
It is also an object of the invention to provide a combined filter and skimmer assembly for ponds which is fully submersible in an existing pond.
It is another object of the invention to provide a combined filter and skimmer assembly for ponds which does not require any excavation to be installed.
It is still another object of the invention to provide a combined filter and skimmer assembly for ponds which does not require unsightly apparatus to be located adjacent to the pond.
It is yet another object of the invention to provide a combined filter and skimmer assembly for ponds which is modular and can be expanded to suit ponds of different sizes.
It is a further objection of the invention to provide a combined filter and skimmer assembly for ponds having a skimmer floating cup which is free to tilt to adjust for an angular difference between the water surface and the top surface of the floating cup.
It is still a further object of the present invention to provide a combined filter and skimmer assembly for a pond having a floating cup which automatically adjusts to the level of the surface of the pond.
In accord with these objects which will be discussed in detail below, the apparatus of the present invention includes a submersible filter box containing replaceable filter media, the filter box having a water inlet, a skimmer coupling, and a water outlet adapted to be coupled to an underwater pump. According to the presently preferred embodiment, the filter box is rectangular with a removable lid. The filter media is located in two sections of the box defined by two rows of baffles which are spaced apart to define a channel between the two sections. The water outlet is preferably aligned with the channel. The lid has a raised central portion wherein lies the water inlet. The water inlet is preferably adjustable as to the size of the inlet. The skimmer coupling is also located in the raised portion of the lid and is spaced apart from the water inlet. According to the presently preferred embodiment, the skimmer coupling is coupled to an upstanding conduit, the end of which is coupled to a skimmer head. The skimmer head preferably includes a floating cup which automatically adjusts to the level of the surface of the pond. Optionally the floating cup is free to tilt to adjust for an angular difference between the surface of the lid and the surface of the pond.